Systems and methods for spraying of sanitizing or disinfecting compositions with improved compatibility

ABSTRACT

This invention relates to systems, methods, and disinfecting compositions for spraying onto surfaces to be sanitized or disinfected. Methods may include providing an aqueous hypohalite disinfecting composition, and providing a spraying system that may include a hand-held spray nozzle through which the composition is sprayed during use, and a pump and associated tubing for conveying the composition to the hand-held spray nozzle. The tubing may be specifically selected to exhibit at least a 65% recovery (no more than 35% loss) of hypohalite after 24 hours of contact between the composition and the tubing. The method may further include conveying the composition from the reservoir to the spray nozzle, and spraying the composition through the nozzle, e.g., onto the target surface. A related system may include similar components. A dilute hypohalite disinfecting composition may be provided for use with the system and/or method. The system may allow interchangeable use of a quaternary amine disinfecting composition.

CROSS-REFERENCE TO RELATED APPLICATIONS

The present application is a divisional of U.S. patent application Ser.No. 15/986,687, filed May 22, 2018, which claims the benefit of U.S.Provisional Patent Application No. 62/511,671, filed May 26, 2017. Eachof the above-referenced applications is hereby incorporated by referencein its entirety.

BACKGROUND OF THE INVENTION 1. The Field of the Invention

The present invention relates to dispensing systems, associated methods,and dilute sanitizing or disinfecting compositions for spraying throughsuch systems and methods. Such compositions may particularly includesanitizing and disinfecting compositions including a sanitizing ordisinfecting active agent, such as a hypohalite.

2. Description of Related Art

Sophisticated spraying systems for spraying a liquid composition areavailable. For example, electrostatic induction charged spraying systemsare available from ByoPlanet, as well as other suppliers. While suchsystems are available, the present inventors have discovered that thereare incompatibility issues when attempting to spray a sanitizing ordisinfecting bleach composition using such available spraying systems.Because of such issues, until now, it was not possible to achievesanitization or disinfection efficacy of a given target surface usingsuch available spraying systems. The present systems, methods andcompositions address such issues.

BRIEF SUMMARY

The present invention relates to spraying systems, methods, and relateddilute sanitizing or disinfecting compositions for dispensing throughthe spraying system. In one aspect, the present invention relates to amethod for dispensing a dilute sanitizing or disinfecting composition(e.g., including a hypohalite sanitizing or disinfecting active agent)through a spraying system. Such a method may include providing anaqueous sanitizing or disinfecting composition, providing a sprayingsystem including a reservoir for holding the aqueous composition, ahand-held spray nozzle through which the composition is sprayed duringuse, and a pump and associated tubing for conveying the bleachcomposition from the reservoir to the hand-held spray nozzle. The tubingmay advantageously be specifically selected to exhibit at least a 65%recovery (i.e., no more than a 35% loss) of hypohalite after 24 hours ofcontact between the sanitizing or disinfecting composition and theassociated tubing. The method further comprises conveying thecomposition from the reservoir to the hand-held spray nozzle andspraying the composition through the hand-held spray nozzle, onto adesired surface.

Another aspect of the present invention relates to a spraying systemspecifically configured for dispensing a dilute sanitizing ordisinfecting composition in an efficacious manner (e.g., while reducinginactivation of the sanitizing or disinfecting active agent within thesystem, so as to provide a desired level of sanitization or disinfectionto the surface being sprayed). The system may include a reservoir forholding the composition, a hand-held spray nozzle through which theaqueous composition is sprayed during use, and a pump and associatedtubing for conveying the aqueous composition from the reservoir to thespray nozzle. Advantageously, the tubing may be specifically selected tohave particular characteristics for ensuring compatibility with ahypohalite (e.g., sodium hypochlorite) sanitizing or disinfectingcomposition, as well as physical characteristics ensuring suitabilityfor use with a peristaltic pump. For example, the tubing may exhibit atleast a 65% recovery (i.e., no more than a 35% loss) of hypohalite after24 hours of contact between the sanitizing or disinfecting compositionand the tubing. The tubing may have a stiffness from 120 lb_(f)/in to135 lb_(f)/in, and a compression force to closure (i.e., that forcerequired to pinch the tubing closed) of from 20 lb_(f) to 30 lb_(f).

Another aspect of the present invention is directed to dilute hypohalitesanitizing or disinfecting compositions, e.g., such as may be used withand/or included within the presently described spraying systems. Thecomposition itself may include water, and a hypohalite salt (e.g.,sodium hypochlorite) at a relatively dilute concentration, such as 85ppm to 200 ppm (e.g., more typically 150 ppm to 200 ppm). The sanitizingor disinfecting composition may have a pH not more than 11.5, or a pH ofnot more than 7 (e.g., less than 11.5, such as 7 to 11, or less than 7,such as 5.5 to 6.7), and the sanitizing or disinfecting composition mayexhibit at least a 65% recovery (i.e., no more than a 35% loss) ofhypohalite after 24 hours of contact between the composition and thetubing of the spraying system. The composition may further be configuredto provide a hypohalite concentration of at least 85 ppm as sprayed ontoa surface to be sanitized or disinfected, upon spraying through thespray nozzle of the spraying system. For example, some fraction of thehypohalite active agent may be lost due to contact with the tubing, andanother fraction of the hypohalite active agent may be lost tovolatilization upon exiting the spray nozzle. Thus, the hypohaliteconcentration of the composition as fed to the spraying system may bespecifically tailored to ensure that a concentration of at least 85 ppmhypohalite is being delivered to the target surface being sanitized ordisinfected.

The various components and parameters of the spraying system, method ofuse, and composition (e.g., tubing materials, composition pH, initialhypohalite concentration in the composition and the like) are thuscarefully selected and controlled to ensure efficacious sanitization ordisinfection of a target surface upon spraying the composition throughthe spraying system. In an embodiment, the spraying system may be anelectrostatic spraying system, in which tiny droplets of the dilutesanitizing or disinfecting composition are electrostatically charged togreatly improve surface coverage of the target surface. Suchelectrostatic spraying ensuring that all surfaces, including theundersides of a given surface, are substantially uniformly coated withthe dilute sanitizing or disinfecting composition.

Further features and advantages of the present invention will becomeapparent to those of ordinary skill in the art in view of the detaileddescription of preferred embodiments below.

BRIEF DESCRIPTION OF THE DRAWINGS

To further clarify the above and other advantages and features of thepresent invention, a more particular description of the invention willbe rendered by reference to specific embodiments thereof which areillustrated in the drawings located in the specification. It isappreciated that these drawings depict only typical embodiments of theinvention and are therefore not to be considered limiting of its scope.The invention will be described and explained with additionalspecificity and detail through the use of the accompanying drawings inwhich:

FIG. 1 is a perspective view showing use of an exemplary spraying systemin an exemplary method of use.

FIG. 2 is a perspective view of the system and method of FIG. 1, fromanother perspective.

FIG. 3 shows stiffness and force to orifice closure characteristics asmeasured for various tubing materials.

FIG. 4 shows sodium hypochlorite concentration for exemplary dilutesanitizing or disinfecting compositions over 80 days, at an elevatedtemperature of 120° F. 25 days at 120° F. approximately correlates to 1year storage at ambient temperature (e.g., 70° F.).

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS I. Definitions

Before describing the present invention in detail, it is to beunderstood that this invention is not limited to particularlyexemplified systems or process parameters that may, of course, vary. Itis also to be understood that the terminology used herein is for thepurpose of describing particular embodiments of the invention only, andis not intended to limit the scope of the invention in any manner.

All publications, patents and patent applications cited herein, whethersupra or infra, are hereby incorporated by reference in their entiretyto the same extent as if each individual publication, patent or patentapplication was specifically and individually indicated to beincorporated by reference.

The term “comprising” which is synonymous with “including,”“containing,” or “characterized by,” is inclusive or open-ended and doesnot exclude additional, unrecited elements or method steps.

The term “consisting essentially of” limits the scope of a claim to thespecified materials or steps “and those that do not materially affectthe basic and novel characteristic(s)” of the claimed invention.

The term “consisting of” as used herein, excludes any element, step, oringredient not specified in the claim.

It must be noted that, as used in this specification and the appendedclaims, the singular forms “a,” “an” and “the” include plural referentsunless the content clearly dictates otherwise. Thus, for example,reference to a “surfactant” includes one, two or more surfactants.

The compositions described herein may provide sanitization,disinfection, or sterilization. As used herein, the term “sanitize”shall mean the reduction of contaminants in the inanimate environment tolevels considered safe according to public health ordinance, or thatreduces the bacterial population by significant numbers where publichealth requirements have not been established. By way of example, an atleast 99% reduction in bacterial population within a 24 hour time periodis deemed “significant.” Greater levels of reduction are possible, asare faster treatment times (e.g., within 1 minute), when sanitizing. Asused herein, the term “disinfect” shall mean the elimination of many orall pathogenic microorganisms on surfaces with the exception ofbacterial endospores. As used herein, the term “sterilize” shall meanthe complete elimination or destruction of all forms of microbial lifeand which is authorized under the applicable regulatory laws to makelegal claims as a “sterilant” or to have sterilizing properties orqualities. Some embodiments of the present compositions provide for atleast a 2 or more log reduction in bacterial population within adesignated time period (e.g., 1 minute, 3 minutes, or the like). A 2-logreduction is equivalent to a 99% reduction, a 3-log reduction isequivalent to at least a 99.9% reduction, a 4-log reduction isequivalent to at least a 99.99% reduction, a 5-log reduction isequivalent to at least a 99.999% reduction, etc.

Unless otherwise stated, all percentages, ratios, parts, and amountsused and described herein are by weight.

Numbers, percentages, ratios, or other values stated herein may includethat value, and also other values that are about or approximately thestated value, as would be appreciated by one of ordinary skill in theart. As such, all values herein are understood to be modified by theterm “about”. A stated value should therefore be interpreted broadlyenough to encompass values that are at least close enough to the statedvalue to perform a desired function or achieve a desired result, and/orvalues that round to the stated value. The stated values include atleast the variation to be expected in a typical manufacturing orformulation process, and may include values that are within 10%, within5%, within 1%, etc. of a stated value. Furthermore, where used, theterms “substantially”, “similarly”, “about” or “approximately” representan amount or state close to the stated amount or state that stillperforms a desired function or achieves a desired result. For example,the term “substantially” “about” or “approximately” may refer to anamount that is within 10% of, within 5% of, or within 1% of, a statedamount or value.

Some ranges may be disclosed herein. Additional ranges may be definedbetween any values disclosed herein as being exemplary of a particularparameter. All such ranges are contemplated and within the scope of thepresent disclosure.

In the application, effective amounts are generally those amounts listedas the ranges or levels of ingredients in the descriptions, which followhereto. Unless otherwise stated, amounts listed in percentage (“%'s”)are in weight percent (based on 100% active) of the composition.

The phrase ‘free of’ or similar phrases if used herein means that thecomposition comprises 0% of the stated component, that is, the componenthas not been intentionally added to the composition. However, it will beappreciated that such components may incidentally form, under somecircumstances, as a byproduct or a reaction product from the othercomponents of the composition, or such component may be incidentallypresent within an included component, e.g., as an incidentalcontaminant.

The phrase ‘substantially free of’ or similar phrases as used hereinmeans that the composition preferably comprises 0% of the statedcomponent, although it will be appreciated that very smallconcentrations may possibly be present, e.g., through incidentalformation, as a byproduct or a reaction product from the othercomponents of the composition, incidental contamination, or even byintentional addition. Such components may be present, if at all, inamounts of less than 1%, less than 0.5%, less than 0.25%. less than0.1%, less than 0.05%, less than 0.01%, less than 0.005%, or less than0.001%. In some embodiments, the compositions may be free orsubstantially free from any components not mentioned within thisspecification.

Unless defined otherwise, all technical and scientific terms used hereinhave the same meaning as commonly understood by one of ordinary skill inthe art to which the invention pertains. Although a number of methodsand materials similar or equivalent to those described herein can beused in the practice of the present invention, the preferred materialsand methods are described herein.

II. Introduction

In an aspect, the present invention is directed to methods and systemsfor dispensing a dilute sanitizing or disinfecting composition through aspraying system. Such a method may include providing an aqueoussanitizing or disinfecting (e.g., including a hypohalite active agent)composition, providing a spraying system, conveying the compositionthrough the spraying system to a hand-held spray nozzle of the sprayingsystem, and spraying the composition onto a target surface to bedisinfected, sanitized, or even sterilized. The term “disinfect” mayprincipally be used in the present detailed description for brevity,although it will be appreciated that the systems, methods andcompositions described herein may provide sanitization, disinfection,and/or sterilization.

The spraying system may include a reservoir for holding the bleachcomposition, a hand-held spray nozzle through which the aqueousdisinfecting composition may be sprayed during use, a pump (e.g., aperistaltic pump) and associated tubing for conveying the disinfectingcomposition from the reservoir to the hand-held spray nozzle. The tubingmay be particularly selected to exhibit at least a 65% recovery ofhypohalite after 24 hours of contact between a disinfecting compositionincluding hypohalite and the associated tubing. Such selection ensuresthat the tubing does not decrease efficacy of the disinfectingcomposition to an unacceptable degree, which might interfere with theability to successfully achieve the desired disinfection.

The present spraying systems, methods and associated compositionsadvantageously provide the ability to deliver a disinfecting compositionincluding an disinfection active agent, such as a hypochlorite salt,another hypohalite, hypochlorous acid, or the like), even where suchagent may typically present incompatibility issues with typical tubingor other typical spraying system components which the compositionincluding the active agent comes in contact with. For example, asdescribed above, the inventors have found that typical materialsemployed in existing spraying systems exhibit an unacceptably highincompatibility level (e.g., very low recovery of hypohalite activeagent) after contact between existing disinfecting compositions and suchtubing or other components. The result is that if one were to use suchexisting systems with existing disinfecting bleach compositions, thedesired disinfection cannot reliably be provided, as too much of thehypochlorite or other active agent is being inactivated before beingsprayed onto the desired target surface to be disinfected. Furthermore,volatilization of such active agent upon exiting the spray nozzle shouldalso be accounted for, as such volatilized active agent is unavailablefor deposition on the target surface being disinfected.

The present systems, methods, and compositions provide specificselections for such components as the tubing of the spraying system, thepH and hypohalite concentration of the bleach composition, and otherfactors to ensure that the desired disinfection does in fact reliablyoccur.

III. Exemplary Spraying Systems, Methods, and Compositions

FIGS. 1-2 illustrate an exemplary spraying system 100, as well as showan associated method of use. System 100 is shown as including areservoir 102, which may be as simple as a jug or other container 102for holding the aqueous disinfecting composition 110. For example, thesystem does not necessarily need to include any dedicated reservoir intowhich the composition 110 is poured, but rather the composition 110 maysimply be provided through tubing 108, which delivers the disinfectingcomposition 110 from container 102 to the remainder of the system 100(e.g., through pump 106, eventually to hand-held spray nozzle 104). Ofcourse, other embodiments of a spraying system could include a dedicatedreservoir separate from a jug or other container in which thedisinfecting composition is provided by a supplier (e.g., such asCLOROX). In such alternative configurations, the disinfectingcomposition could be poured by the user into a dedicated reusablereservoir.

System 100 includes a hand-held spray nozzle 104 through which thedisinfecting composition 110 is sprayed during use. In an embodiment,the hand-held spray nozzle 104 may be configured for electrostaticspraying, e.g., where the composition 110 being sprayed iselectrostatically charged upon exiting nozzle 104 to improve coverage ofthe target surface 112 being sprayed. Examples of such electrostaticspraying systems are described in U.S. Pat. Nos. 5,704,554; 5,765,761;9,138,760; and 9,144,811. Such spraying systems are available fromBYOPLANET, located in Sunrise, Fla. Of course, any other spraying systemcould alternatively be used, whether an electrostatic spraying system orotherwise. Electrostatic spraying systems may be preferred because ofthe improved coverage and efficacy associated with such systems.

FIGS. 1-2 illustrate how spraying system 100 may be configured as aportable wheeled cart, including a power source (e.g., such as powercord 114) for providing power for powering pump 106, as well asproviding power for induction charging to achieve electrostatic sprayingof the composition through hand-held nozzle 104. Such configuration ismerely exemplary, as a wide variety of spraying systems may suitablyincorporate the principles described herein.

FIG. 2 shows system 100 including a pump 106 and associated tubing 108for conveying the bleach composition 110 from container 102 to hand-heldspray nozzle 104. At least a portion, and preferably all such tubing 108exhibits at least a 65% recovery (i.e., no more than a 35% loss) ofhypohalite after 24 hours of contact between the disinfectingcomposition and the tubing 108 (e.g., as measured at 70° F.). By way ofexample, the tubing may be specifically selected to exhibit at least a65% recovery, at least a 70% recovery, at least a 75% recovery, orhigher recovery. In other words, the tubing may be selected to exhibitno more than a 35% loss, no more than a 30% loss, or no more than a 25%loss, after 24 hours of contact between the tubing 108 and thedisinfecting composition 110.

For example, the present inventors found that typical tubing materialsemployed in existing spraying systems exhibit lower, unacceptablerecovery values, such as less than 60% recovery (i.e., more than a 40%loss) of hypochlorite or other hypohalite. The tubing materialsaccording to the present invention are therefore specifically selectedto ensure higher recovery (i.e., lower loss) of the hypochlorite orother hypohalite active agent in the disinfecting composition. Forexample, the present inventors have found that plasticizers and/or otheradjuvants included in tubing materials typical employed in sprayingsystems are incompatible with the hypochlorite or other active agent(s),leading to the unacceptable levels of disinfecting active agent loss.

The selected tubing should thus meet various particular parameters inorder to be suitable for use within the present spraying systems andmethods. In addition to the above described need for minimal or at leastreduced inactivation of the hypochlorite disinfecting active component,the tubing in at least some embodiments should be transparent ortranslucent, rather than opaque. Such a characteristic advantageouslyallows the user to view the composition passing through the tubing, onits way to the hand-held spray nozzle. Such ability to view the flow ofcomposition through the tubing aids the user in ensuring that properflow (e.g., no clogging, etc.) is occurring.

In addition, the selected tubing may be required to meet particularcharacteristics relative to its flexibility and durability, particularlywhere the pump employed in the spraying system is a peristaltic pump,such as peristaltic pump 106 shown in FIG. 2. Peristaltic pumps will befamiliar to those of skill in the art, and typically include a rotorwith one or more rollers (also referred to as “shoes) attached to therotor, which rollers compress the flexible tube which passes around therotor of the peristaltic pump, along a relatively tight radius ofcurvature (e.g., no more than about 6 inches, no more than about 5inches, no more than about 4 inches, no more than about 3 inches. Forexample, as shown in FIG. 2, a peristaltic pump 106 that requires thetube to bend around a 6 inch circle would require the tubing to bendwith a radius of curvature of 3 inches. As the rotor turns, the rollercompresses the tubing 108, pinching it closed and forcing the fluidtherein to move through the tubing 108.

Within spraying systems including a peristaltic pump according to thepresent invention, the inventors have found that it is advantageous thatthe tubing 108 contacted by the rollers of the peristaltic pump 106 havea stiffness that is from 120 lb_(f)/in to 135 lb_(f)/in. Somewhatrelated to tube stiffness, the selected tubing 108 may exhibit acompression force to closure that is from 20 lb_(f) to 30 lb_(f). Suchcompression force to closure refers to the force needed to cause theorifice within the tubing 108 to close (i.e., the pinching forcerequired to close the orifice of the tube). Where the tubing material istoo stiff and/or exhibits too high of compression force to closure, therollers of a peristaltic pump 106 may not be able to effectivelycompress the tubing and pinch it closed to achieve the desired fluidflow. Where the tubing material has very low stiffness and/orcompression force to closure is too low, pressure build up may occurwithin the tubing, causing the fluid in the tube to continue to spurteven after the user has finished spraying. In addition, tubing with verylow stiffness and/or very low compression force to closure may notexhibit sufficient robustness or durability for use with a peristalticpump. For example, ripping and/or shredding of the tubing material mayoccur after only a relatively short period of operation where the tubingmaterial is not sufficiently stiff.

There is thus something of a delicate balance required to ensure thatthe tubing material is sufficiently stiff to ensure robustness anddurability so as to provide long service life when used with aperistaltic pump, but not so stiff as to be incapable of accepting theneeded tight radius of curvature as the tubing wraps around theperistaltic pump. The tubing 108 cannot be so stiff as to be toodifficult to compress, forcing the orifice to close, as this will makeuse with a peristaltic pump impractical if not impossible, and thetubing 108 cannot exhibit a very low force to closure, which has beenfound to be associated with undesirable spurting of the composition evenafter use of the spray nozzle has stopped, because of a build up ofpressure within the tubing 108. Finally, the tubing needs to exhibit lowloss of hypohalite active agent upon contact with the disinfectingcomposition. As such, it is important to select the particular tubingmaterial with care, to ensure that it meets the lengthy list ofimportant criteria. Tubing materials currently employed in peristalticpump spraying system applications do not meet such criteria.

In addition to the above criteria for tubing 108, the tubing may have adurometer value of 60 to 75, on the Shore A scale. While durometer canbe helpful in identifying a suitable tubing material, durometer valueonly captures the response of the tubing material to indentation of thetubing wall, which characteristic appears to be insufficient to fullyidentify a material exhibiting acceptable stiffness and flexibilitycharacteristics, as will be apparent from the exemplary testedmaterials, described in conjunction with Table 1, below. For example,VITON tubing has a durometer value of 60 to 75 on the shore A scale, butin testing, this tubing material was found to have too low of stiffness(less than 60 lb_(f)/in) and compression force to closure that was alsotoo low (13.3 lbf). Before the importance of the stiffness andcompression force to closure criteria were recognized by the presentinventors, VITON was identified as a prospective suitable tubingmaterial, based on its durometer value. When tested for use in aperistaltic pump, however this tubing material caused the composition tospurt even after spraying was finished, and the tubing material rippedup within 72 hours of usage under test conditions when used with aperistaltic pump. While the durometer value appeared to be acceptable,the stiffness and force to closure values (unrecognized at the time)were unacceptable. The inventors' experience with the VITON tubingmaterial helped in identification of the above described criteriarelating to stiffness and compression force to closure.

Other physical characteristics may also be of some utility foridentifying suitable tubing materials. For example, tensile strength isthe maximum stress a material can withstand while stretching or pulling,before breaking. Ultimate elongation is the maximum length a materialcan be stretched before breaking. Compression is another possiblecharacteristic. Compression set for tubing materials describes to whatextent the tubing will recover to its original shape after beingcompressed for an extended period of time under a heated condition.According to one test, a sample is compressed 25% at 70° C. for 22 hoursto determine compression set (i.e., percentage of the originaldeflection retained after the material is allowed to recover at standardconditions (e.g., 20° C.) for 30 minutes. While such characteristics maybe helpful to some extent, the present inventors have found thatstiffness values, compression force to closure, and hypochlorite lossare far more useful in identifying potential suitable tubing materials.

As described above, the stiffness of suitable tubing materials,particularly for use with a peristaltic pump, may be from 120 lb_(f)/into 135 lb_(f)/in. Stiffness measures the amount that a material resistsdeformation from an applied force. Stiffness can be measured by applyinga force in one direction and measuring the rate of force per length ofdisplacement. In compressing tubing at a constant rate of motion (e.g.,as in a typical peristaltic pump), the rate of force per unit distancewill give stiffness of the tubing material in the sidewall. Test resultsfor such testing are shown in FIG. 3. The slope of the initial rise ofthe various curves shown in FIG. 3 thus corresponds to the stiffness ofthe various tested tubing materials. The force at which the ratesignificantly increases (i.e., the inflection point) corresponds to thecompression force required to complete orifice closure. After thispoint, the compressive force is merely compressing the plastic tubing.

The stiffness and compression force to closure shown in FIG. 3 and inTable 1 were determined by placing tubing samples flat along the bottomplate of an INSTRON testing machine. The INSTRON top plate (3″×0.5″) wasplaced immediately above the tubing, perpendicular to the direction ofthe tubing. The top plate was lowered at a rate of 1 inch/minute until amaximum load of 300 lb_(f) was reached, and then the plate was liftedagain. The slope (in lb_(f)/in) (corresponding to the stiffness of thetubing material) was determined by compressing the top wall of the tubeinto eventual contact with the lower tube wall. The load at which theslope changed due to compression of the abutting tube walls signals thepoint of orifice closure. The tubing dimensions for all but the PVCmaterial were ⅛″ ID, ¼″ OD. The PVC tubing material that was tested was3/16″ ID, 5/16″ OD. It will be appreciated that any size tubing could beused.

As described above, a peristaltic pump typically operates byalternatingly compressing and relaxing the tubing in a circular pumpcasing (e.g., see pump 106 of FIG. 2) to draw the contents of the tubing108 through the tube. Generally such pumps include two rollers(sometimes referred to as shoes) which rotate at the same rate. Once aroller touches the tubing 108, it compresses the tubing completely(closing the orifice). As it rotates, it pushes the fluid through thetubing. Because of the physical demands imposed by such a pump system,it is important that the tubing material be elastomeric. Furthermore,where the composition is a disinfecting composition including ahypochlorite or other disinfecting active agent, the tubing needs to bechemically resistant to the composition being delivered therethrough, asdescribed herein.

Existing spraying systems typically include multiple tubing sections,what at least two different materials are used for the various tubingsections. Such construction is typical to provide tubing that isappropriate to the flexibility and other needed characteristics for thegiven tubing section. For example, EXCELON RNT tubing material iscurrently used within existing spraying systems for the tubing sectionassociated with the peristaltic pump, due to desirable flexibility,stiffness, and durability characteristics. The present inventors foundthat such tubing undesirably interacts with the hypohalite active agentin the disinfecting composition, due to the presence of plasticizers inthe tubing material.

As a first iteration, the present inventors tested EXCELON RNT tubing inthe peristaltic pump section, and low density polyethylene (LDPE) forthe rest of the liquid tubing sections, because polyethylene has goodchemical resistance, and would be less likely to interact with thebleach active agent. This was found to be impractical, because LDPE isrelatively inflexible, making it difficult to work with, even in thetubing sections separate from the peristaltic pump. As a result of thedifficulties of this first iteration, various other tubing materialswere evaluated for stiffness versus flexibility, force to orificeclosure, compatibility with hypochlorite active agents, and othercharacteristics. The results are shown in Table 1.

TABLE 1 Com- pression % OCl⁻ Stiff- Force to Tensile Re- ness ClosureDuro- Strength Clear/ Tubing covered (lbf/in) (lbf) meter (psi) OpaqueVERSILON 100.87%  766.57 102.33 D43 opaque DUALITY HDPE 99.2%  D65opaque TYGON 98.06% 125.32 25.22 A67 2000 clear SE-200 VERSILON 96.01%D58 clear PTFE LLDPE 90.96% D44 opaque VITON 88.80% 59.15 13.31 A60-751450 opaque VITUBE TYGON 86.27% 213.91 29.76 A72 2000 clear 2475 HIPURITY TYGON 76.30% 132.16 24.24 A69 800 clear 2001 TYGON 74.28% A751900 clear 2375 EXCELON 59.55% A68 clear RNT SILICONE 26.36% A50 1100opaque ¼″

As will be apparent, many of the tubing materials that are availablethat provide the highest recovery of hypochlorite active agent wererelatively inflexible, or very difficult to compress, making themunsuitable for use in a peristaltic pump application. At this stage, theVITON, TYGON 2001, AND TYGON SE-200 seemed appropriate based onflexibility values and hypochlorite recovery.

While the VITON tubing showed hypochlorite recovery of over 88% after a24 hour soak, this recovery value dropped to about 75% after a 2 weeksoak. TYGON 2001 tubing showed a hypochlorite recovery of 76.3% after a24 hour soak. Based on these initial data, VITON tubing was testedwithin the spraying system with a peristaltic pump, and several problemswere noted. Pressure build up occurred in the tubing, even afterspraying was finished, causing the composition to continue to “spurt”out, after spraying had finished, as mentioned above. Perhaps mostimportantly, the VITON tubing material ripped apart within 72 hours oftest use within the peristaltic pump, which was likely due to frictionbetween the rollers and the tubing. In addition because the VITON tubingis opaque, the user could not see the liquid flow within the tubing.

Because of the difficulties with the VITON tubing material, the TYGON2001 material was tested, and found to be suitable for use. It exhibitshypochlorite recovery of 76.3% after 24 hours of contact, it is clear(which advantageously allows the user to view flow of the compositionthrough tubing 108), it includes a stiffness value that is between from120 lb_(f)/in and 135 lb_(f)/in, and it includes a force to closurevalue that is between from 20 lb_(f) and 30 lb_(f). Such characteristicshave been found by the present inventors to provide sufficientdurability and robustness, while also being sufficiently flexible foruse with a peristaltic pump. This tubing material exhibited acceptablecompatibility with hypochlorite bleach, as well as high compatibilitywith an alternative quaternary amine disinfecting agent. For example, inat least some embodiments, the present spraying systems and methodsallow for use of either a hypohalite-based disinfecting composition, ora quaternary amine-based disinfecting composition. The tubing materialsand other parameters identified herein allow use of either or both suchcompositions, interchangeably, allowing the system and method to becompatible and easily usable with either such disinfecting composition.

An example of such an alternative quaternary-amine based disinfectingcomposition is available from STEPAN under the EPA registration1839-220. By way of example, such a composition includes as activeingredients, a mixture of alkyl dimethyl benzyl ammonium chlorides and amixture of alkyl dimethyl ethylbenzyl ammonium chlorides. For example,the particular formulation associated with EPA registration 1839-220includes 0.15% of each of the above classes of quaternary ammoniumcompounds. The mixture of alkyl dimethyl benzyl ammonium chloridesincludes alkyl chain lengths of 60% C₁₄, 30% C₁₆, 5% C₁₂, and 5% C₁₈.The mixture of alkyl benzyl ammonium chlorides includes alkyl chainlengths of 68% C₁₂ and 32% C₁₄. It will be apparent that otherquaternary amine compounds, mixtures of various quaternary amines, orother disinfecting agents may alternatively or additionally be used.While the above example includes 0.3% quaternary amines, it will beapparent that the range of quaternary amine disinfecting agent may vary,e.g., from about 0.01% to about 2%, or from 0.05% to about 1%, or from0.1% to about 0.5% by weight.

Returning to the description of tubing materials, the present inventorsdiscovered that tubing materials cannot be easily selected forapplications including a peristaltic pump, particularly for uses inwhich contact with hypochlorite or other hypohalite bleach disinfectingagents will occur. Tubing properties provided in manufacturerspecification sheets, such as durometer hardness, tensile strength, andcompression set do not provide sufficient information to determine if atubing material will be suitable for use in a peristaltic pumpapplication, not to mention whether such tubing material will exhibitsufficient compatibility with a quaternary amine or hypohalitedisinfecting agent. The specific properties measured and recorded above(e.g., such as stiffness and force to orifice closure) far are morerelevant to indicating whether the material will be suitable for use inan application including a peristaltic pump. In addition, as theinventors found, most types of tubing which have minimal interactionwith hypohalite disinfecting agents (e.g., HDPE, LDPE, PET) are far toostiff and inflexible for use in such applications.

The inventors discovered something of a “sweet spot” with respect tostiffness and force to closure is needed in order to provide sufficientdurability and robustness for use in peristaltic pump uses, while alsoproviding sufficient flexibility to allow the tubing material to bebent, flexed, and manipulated as needed by the user during operation(not to mention the ability to wrap around a peristaltic pump at arelatively tight curvature, as seen in FIG. 2). As noted above, valuesof stiffness that are from 120 lb_(f)/in to 135 lb_(f)/in, (e.g., from122 lb_(f)/in to 133 lb_(f)/in) and force to closure values that arefrom 20 lb_(f) to 30 lb_(f) (e.g., from 22 lb_(f) to 26 lb_(f))advantageously allow the tubing material to balance the neededcharacteristics. Exemplary materials listed in Table 1 including suchcharacteristics, while also providing a hypochlorite recovery of atleast 65% (a loss of no more than 35%) include at least TYGON SE-200 andTYGON 2001. The stiffness and force to closure values of some of thematerials listed in Table 1 were not yet tested (e.g., TYGON 2375), butmay prove suitable for use, so long as they exhibit stiffness and/orforce to closure values as noted above. In addition, it will beappreciated that various other tubing materials may also meet theidentified requirements.

Both TYGON SE-200 and TYGON 2001 are proprietary, clear PVC materials,which may be specially formulated to reduce or eliminate the inclusionof plasticizer materials within the tubing material. Other TYGON tubingmaterials (e.g., TYGON 2375) are also believed to be formed from PVC,without incompatible plasticizers. It is believed that plasticizersroutinely added to such PVC tubing materials (e.g., such as in theEXCELON RNT tubing) are incompatible with the hypochlorite or otherhypohalite active agent included in a hypohalite-based disinfectingcomposition. TYGON SE-200 is believed to include a fluorinated ethylenepropylene liner or layer over the base PVC material.

TYGON 2001 is described as being plasticizer and oil free, and meets theFDA criteria for food contact. Other suitable TYGON tubing materials mayalso exhibit similar characteristics. TYGON 2001, TYGON SE-200, andTYGON 2375 have the following physical characteristics, as shown belowin Table 2. While at least TYGON 2001 and TYGON SE-200 are suitablematerials for use within the presently described spraying systems andmethods, where a peristaltic pump is employed, it will be appreciatedthat other tubing materials meeting the above described keycharacteristics relative to stiffness, compression force to orificeclosure, and hypochlorite recovery may also be suitable for use.

TABLE 2 ASTM TYGON TYGON TYGON Property Method 2001 SE-200 2375Durometer Shore D2240-03 69 75 A Color — Clear Clear Clear TensileStrength D412-98 800 2000 1900 (psi) Ultimate D412-98 500 350 850Elongation, % Tear Resistance D1004-03 140 165 240 (lb_(f)/M) SpecificGravity D792-00 0.88 1.45 0.9 Water Absorption D570-98 0.04 <10.01 <0.01(24 hrs @ 23° C.) Compression Set D395-03 40 53 100 Constant MethodDeflection, % @ B 70° C. for 22 his Brittleness by D746-98 −78 −40 <−75Impact Temp (° C.) Maximum — 57 77 54 Recommended Operating Temp. (° C.)Low Temp. D380.94 −73 — −75 Flexiblilty (° C.) Dielectric StrengthD149-97 530 620 — (V/mil) Tensile Modulus D412-98 240 650 425 @ 100%Elongation, psi Tensile Set, % D412-98 110 76 300 * Unless otherwisedictated, all tests were conducted at room temperature (73° F). Valuesshown were determined on 0.075″ thick extruded strip or 0.075″ thickmolded ASTM plaques or molded ASTM durometer buttons.

While the disinfecting compositions may be based on a salt ofhypochlorite (e.g., sodium hypochlorite) as the disinfecting agent, itwill be appreciated that other disinfecting agents can alternatively oradditionally be used. Non-limiting examples of such include otherhypohalites (e.g., hypobromides, or other halides), other chlorinegenerating compounds (e.g., isocyanates and the like), hypohalous acids(e.g., hypochlorous acid), halogens, peroxides (e.g., hydrogenperoxide), and/or quaternary amines, and the like. Examples ofhypochlorites include, but are not limited to alkali metal hypochlorites(e.g., sodium hypochlorite, potassium hypochlorite, and the like, alkaliearth metal hypochlorites (e.g., calcium hypochlorite, magnesiumhypochlorite, and the like). Combinations of hypochlorites may of coursebe employed.

The composition may have a viscosity so that it may readily be dispensedthrough a spraying system as described herein. For example, thecompositions may have a viscosity of less than 10,000 cps, less than1,000 cps, less than 100 cps, or less than 10 cps. In an embodiment, theviscosity may be approximately equal to that of water (e.g., 1 cps).

In an embodiment, particularly where the disinfecting compositioncontains a hypochlorite active agent, the pH may be less than 8, or lessthan 7. Even though hypochlorite active agents typically exhibitincreased stability at elevated pH values (e.g., greater than 8, such as9 to 13, or 9 to 12), in at least some embodiments, the disinfectingcomposition including a hypohalite active agent is specificallyformulated to have a pH that is less than 8, or no more than 7, whilestill exhibiting good stability, and exhibiting higher microefficacyagainst bacteria, viruses or other microbes on a target surface beingsprayed. For example, while hypohalites (e.g., sodium hypochlorite) maytypically exhibit higher stability at relatively higher pH values, themicroefficacy may be improved at somewhat lower pH values. The pKa valuefor sodium hypochlorite bleach solution is at about a pH of 7.4, meaningthat this is the most unstable pH for such dilute hypochloritesolutions. As such, the disinfecting composition may have a pH of nomore than 7, less than 7, no more than 6.7, from 5 to 7, from 5.5 to 7,from 5.5 to 6.7, from 6 to 7, from 6 to 6.7, or from 6 to 6.5.

FIG. 4 illustrates the effect of pH on hypohalite stability over time,at an elevated temperature of 120° F. FIG. 4 also shows the effect ofthe container material (e.g., HDPE or PET) on hypohalite stability. Asshown in FIG. 4, by ensuring that the composition has a lower pH (e.g.,pH of 6 to 6.7, or 6 to 6.5), loss of hypochlorite within the container(e.g., during storage, over the expected shelf-life of the composition)can be minimized or reduced to an acceptable degree. By way of example,a shelf life of the composition may be determined by the time it takesfor the hypohalite concentration to drop to 120 ppm. 25 days at anelevated temperature of 120° F. may be approximately equivalent to 1year of shelf-life at 70° F. As will be apparent from FIG. 4, using anappropriate container material and maintaining the dilute disinfectingcomposition at a pH of no more than 7 (e.g., no more than 6.7, or nomore than 6.5) can achieve an expected 1 year or better shelf-life. Aconfiguration as represented in FIG. 4, including an initialhypochlorite concentration of 160 to 165 ppm, and a pH of 6.7 or less issufficient to ensure surface sanitization (e.g., at least 85 ppmhypochlorite as deposited on the target surface) even after 1 year ofstorage of the composition, under typical storage conditions.

The disinfecting composition may be dilute, such that it exhibits only arelatively low level of hypohalite concentration. For example, theconcentration of hypohalite in the composition may be not greater than500 ppm, not greater than 400 ppm, not greater than 300 ppm, not greaterthan 210 ppm, or not greater than 175 ppm. The concentration ofhypohalite may be at least 85 ppm, at least 100 ppm, at least 120 ppm,or at least 150 ppm, e.g., from 150 ppm to 175 ppm, or 120 ppm to 210ppm. While such dilute concentrations may be particularly suitable, itwill be appreciated that higher concentrations may be suitable for usein at least some circumstances (e.g., up to 1,000 ppm, up to 2,000 ppm,or even up to 5,000 ppm).

For ease of use, the disinfecting composition may be provided at such adilute hypohalite concentration, so that the user and/or spraying systemdoes not need to further dilute the composition. Of course, it is withinthe scope of the present disclosure to provide a more concentratedcomposition, which may be diluted by the user and/or diluted by thespraying system (e.g., automatically, by mixing the concentrate withwater) before spraying.

Upon spraying the disinfecting composition (e.g., as seen in FIG. 1),the concentration of hypohalite within the composition as sprayed ontothe target surface may be at least 85 ppm, in order to provide thedesired level of surface sanitization or disinfection. For example, evenwhere the concentration of hypochlorite in the composition as it exitsthe spray nozzle is greater than 85 ppm (e.g., from 120 to 210 ppm),some fraction (e.g., as much as 20%) of the hypochlorite or other activeagent may actually volatilize, and be lost, rather than reaching thesurface 112 being treated. As will be apparent from the presentdescription, some fraction of the hypochlorite may also be lost throughcontact with the tubing 108, or through other undesirable interactions.Thus, in at least some embodiments, the composition as provided to theuser (e.g., in reservoir 102) may have a hypochlorite or otherhypohalite concentration of 150 to 175 ppm, ensuring that theconcentration actually reaching the target surface being sprayed is atleast 85 ppm, even after 1 year of storage of the disinfectingcomposition (e.g., at which point the hypohalite concentration thereinmay have dropped to as low as 120 ppm). Even where some losses may occurwithin the spraying system itself (e.g., within tubing 108), and somehypohalite may be lost to volatilization upon exiting nozzle 104, suchlosses can be accounted for and acceptably accommodated, to still ensurean efficacious deposition of at least 85 ppm hypohalite.

The system, method, and composition may be configured to providedispensed disinfection composition having particular particle size, andunder particular air flow characteristics. For example, flow may be from75 mL/min to 200 mL/min, 100 mL/min to 150 mL/min, or from 120 mL/min to130 mL/min. Air pressure may be from 15 psi to 100 psi, from 25 to 50psi, or from 30 psi to 40 psi. Air flow may be from 1 standard cubicfeet per minute (SCFM) to 10 SCFM, from 2.5 SCFM to 5 SCFM, or from 3SCFM to 4 SCFM. The parameters may be particularly selected to providean average particle size for dispensed droplets having a size greaterthan 50 μm, greater than 60 μm, or greater than 65, e.g., from 50 μm to150 μm, from 60 μm to 100 μm, or from 65 μm to 80 μm.

While principally described in the context of a disinfecting compositionincluding a hypohalite (e.g., sodium hypochlorite) disinfecting agent,it will be appreciated that the present systems and methods are alsosuitable for use with disinfecting compositions that include aquaternary ammonium disinfecting agent. The present systems and methodsthus allow a user to use either of such disinfecting compositions,interchanging between the two, and using whichever is desired, at anyparticular time or use.

The disinfecting compositions may include one or more surfactants,solvents, organic or mineral acids, chelating agents, fragrances, dyes,preservatives, humectants, polymers, pH adjusters, buffers,solubilizers, or other adjuvants employed in disinfecting compositions.

Examples of surfactants include, but are not limited to sulfates,sulfonates, betaines, alkyl polysaccharides, (e.g., alkylpolyglycosides, also known as alkyl polyglucosides), amine oxides,tweens, alcohol ethoxylates, and combinations thereof. The surfactantconcentration may be any desired concentration. Examples may include upto 80%, up to 50%, up to 30%, up to 20%, or less than 10%, less than 5%,less than 4%, less than 3%, or less than 2% by weight, depending on thecharacteristics desired.

The surfactant(s) may include nonionic, anionic, cationic, ampholytic,amphoteric, zwitterionic surfactants, and mixtures thereof. A typicallisting of anionic, ampholytic, and zwitterionic classes, and species ofthese surfactants, is given in U.S. Pat. No. 3,929,678 to Laughlin. Alist of cationic surfactants is given in U.S. Pat. No. 4,259,217 toMurphy. Various alkyl polysaccharide surfactants are disclosed in U.S.Pat. No. 5,776,872 to Giret et al.; U.S. Pat. No. 5,883,059 to Furman etal.; U.S. Pat. No. 5,883,062 to Addison et al.; and U.S. Pat. No.5,906,973 to Ouzounis et al. U.S. Pat. No. 4,565,647 to Llenado. Variousnonionic surfactants can be found in U.S. Pat. No. 3,929,678 toLaughlin. Each of the above patents is incorporated by reference.

An organic acid (e.g., citric acid), or relatively weaker mineral acid(e.g., phosphoric acid) may be included, e.g., for pH adjustment, forcleaning, or the like. Where included, such an acid may be included inan amount of less than 5%, less than 4%, less than 3%, less than 2%,less than 1%, less than 0.5%, (e.g., from 0.01% to 2%, or from greaterthan 0.1% to about 1.5%).

Exemplary organic acid may include 2-hydroxycarboxylic acids or mixturesof two or more acids. Examples of such acids include, but are notlimited to, tartaric acid, citric acid, malic acid, mandelic acid,oxalic acid, glycolic acid, lactic acid, and acetic acid.

If it were desired to adjust pH upward, a basic pH adjuster (e.g.,sodium hydroxide, or another hydroxide), could be used, e.g., in any ofthe amounts described above relative to pH adjusting acids.

Solubilizers (e.g., to solubilize a fragrance or other oil), if present,could be included in an amount of less than 1%, less than 0.5%, lessthan 0.3% (e.g., from about 0.01% to 0.5%).

Dyes, fragrances, and/or preservatives, if present, may be included inan amount of less than 1%, or less than 0.5%.

The compositions, methods, and systems may be particularly well suitedfor use in public or commercial environments, such as airports,ambulances, gyms and other athletic facilities, bathrooms, correctionalfacilities, cruise ships, daycare centers, health clubs, hotels,institutional kitchens, laundry rooms, offices, restaurants, andschools, to name just a few. Of course, use in the home or otherlocations may also be appropriate.

Without departing from the spirit and scope of this invention, one ofordinary skill can make various changes and modifications to theinvention to adapt it to various usages and conditions. As such, thesechanges and modifications are properly, equitably, and intended to be,within the full range of equivalence of the following claims.

1. A dilute hypohalite sanitizing or disinfecting composition for use in a spraying system for dispensing the dilute hypohalite sanitizing or disinfecting composition through the spraying system, wherein the spraying system includes a hand-held spray nozzle through which the aqueous hypohalite sanitizing or disinfecting composition is sprayed during use, and a pump and associated tubing for conveying the aqueous hypohalite sanitizing or disinfecting composition from a reservoir to the hand-held spray nozzle, the dilute hypohalite sanitizing or disinfecting composition comprising: (a) water; and (b) a hypohalite at a concentration from 150 ppm to 200 ppm; (c) wherein the hypohalite bleach composition has a pH of no more than 7; (d) wherein the dilute hypohalite bleach composition exhibits at least a 65% recovery of hypohalite after 24 hours of contact between the hypohalite bleach composition and the associated tubing of the spraying system; (e) wherein the aqueous hypohalite sanitizing or disinfecting composition maintains a concentration of hypohalite of at least 85 ppm as sprayed onto a target surface to be sanitized or disinfected.
 2. The composition of claim 1, wherein the hypohalite sanitizing or disinfecting composition has a pH from 5.5 to not more than 11.5.
 3. The composition of claim 1, wherein the hypohalite sanitizing or disinfecting composition has a pH from 5.5 to 6.7.
 4. The composition of claim 1, wherein the hypohalite has a concentration that is not greater than 175 ppm.
 5. The composition of claim 1, wherein the aqueous hypohalite sanitizing or disinfecting composition has a concentration of hypohalite that is not greater than 5,000 ppm, not greater than 500 ppm, not greater than 200 ppm, or not greater than 175 ppm. 